Polyester resins are one of the two generally used chemistries in emulsion aggregation (EA) techniques for constructing toners for imaging devices. For example, sulphonated polyester resins self-assemble to form nanoparticles in an aqueous medium. With at least 4 mole % up to 20 mole % of a sulphonated diol or a sulphonated diacid monomer, the resulting polymer chains in an aqueous medium at elevated temperatures demonstrate chain association and assemble into nanoparticles ranging in size from about 30 to about 50 nm on cooling. The resulting emulsions are used in the EA process to produce micron-sized polyester toner particles. The development of sulphonated polyester EA toners is described, for example, in U.S. Pat. Nos. 6,830,860; 7,312,011; and 7,335,453, herein incorporated by reference in entirety.
U.S. Pat. No. 7,749,672 and U.S. Publ. Nos. 2010/0222521 and 2011/0014564 teach polyesters with a single terminal carboxylic acid group.